Structure Revision of an Acorane Sesquiterpene Cordycepol A.

Structure revision of a recently reported spirodecane sesquiterpene, cordycepol A, from fungi Cordyceps ophioglossoides was enabled by fast and accurate calculations of nuclear spin-spin coupling constants (SSCCs) with a relativistic force field (DU8c) parametric method. Two other reported cordycepols, B and C, are also identified as misassigned. Calculations of accurate SSCCs, which contain a wealth of structural information, offer a chemically intuitive tool for structure elucidation, rendering the whole structure revision process more guided and intentional, while augmenting in a synergistic way the calculations of chemical shifts.